When using alt (alone or with another character) in user key bindings the show/hide/focus behaviour of the menu control is still present.

For example, with the menu hidden the keystroke 'alt+s' will cause the menu to appear regardless of user-specified binds to the same keystroke. I assume this is intentional behaviour to allow access to the menu when it is hidden, but it restricts the ability to bind anything to any alt combinations associated with the menu.

There doesn't seem to be any reference to menu behaviour in the default keybinds so I thought it might be worth posting here.